Instant messaging may not be the communications dynamo it was a few years ago, but it's still and fast and easy way to connect with friends, family members, and coworkers.

Indeed, I've relied on it for ages to chat with busy editors, and I especially love being able to review message histories to recall what was discussed and when. It's also a great way to reach the tech-support guy who handles my Web hosting -- no waiting indefinitely for an email reply (which is especially important when email is not working).

Screenshot by Rick Broida/CNET

Just one problem: Different people use different IM services. Your contacts might be spread out across AIM, Facebook, Skype, Yahoo, and other platforms. Needless to say, it would be quite a hassle for you to have to install the software needed to accommodate all those services, or even just to sign into them within various browser tabs.

Fortunately, you don't have to. All you need is a cross-platform messaging system that lives in your Web browser. That's the good news; the bad news is that these systems seem to be vanishing. Last year, Google-acquired Meebo shut down its last remaining tools, and Imo just announced plans to do likewise. But there's at least one option left, one IM service to rule them all.

It's called IM+. When you first visit the site, you have the option of signing up for a free account (via email or Facebook), though you can also bypass the whole account thing and just choose an IM service you want to sign into straight away.

The benefit to creating an IM+ account is that it will remember all your other IM accounts -- and automatically sign you into them on subsequent visits.

Screenshot by Rick Broida/CNET

You can also install the IM+ Bar, a browser add-on that's available for Chrome, Firefox, Opera, and Safari. (Sorry, Internet Explorer users -- you're stuck running IM+ in a tab. Not that there's anything wrong with that.) IM+ also offers mobile apps for chatting on your smartphone or tablet, with versions for all the major platforms.

If you just want to take IM+ for a test drive, though, click the icon for any of the listed chat services -- Facebook, Google Talk, MSN -- or click More for a longer list of services (including AIM and Jabber). After supplying your username and password, IM+ will get you connected, and you should see a list of your contacts. Click any of them to start a chat session.

Of course, the real power of IM+ is the option of signing into multiple services simultaneously. Again, you can do this with or without an IM+ account; just click the plus sign in the upper-right corner, then choose the next chat service you want to sign into. Wash, rinse, and repeat as desired.

And that's about it. If you've found a better unified solution for accessing multiple chat services, share it in the comments!